Bump.
Do you really not draw any other conclusions whatsoever from that data?
Is it really that irrelevant?
OMFSM...
Merged Discussion of femr's video data analysis
- Thread starter tfk
- Start date
Do you really not draw any other conclusions whatsoever from that data?
Is it really that irrelevant?
OMFSM...
I agree. Arduous discussion most of the time
Really shouldn't be.Most here are bizarrely convinced that is my nefarious scheme, even going so far as to call it propoganda
It is the NIST 5.4s time period they determined using the Cam#3 viewpoint, but graphed using data from the Dan Rather viewpoint synchronised correctly.
It highlights to me that the NIST T0 value was early. (The flat bit at the start of the graph)
From WTC7 trace data, all sorts of things. Early motion data has been very useful. Determining initial flexure
has been very useful.To challenge NIST ? What are you talking about ? I criticise NIST where appropriate, sure, but that's not the be-and-end-all
Sounds like you are falling back into the *big picture*. Don't do it here please.NIST did not define T0 manually. They used the brightness of a pixel in region (A). They could not use a pixel above region (B) because the rooftop structures were still there.
Therefore, as they have T0 set at the 0 in their graphs they must have spliced the T0 definition data with the trace from above region (B) which they must have started at a latter point in time.
Are you going to accept what I've just had to repeat a number of times in the last hour or so now ?
<tips hat>
It's only really *current* as I was trying to help, er, others. Am just having to go over old ground again as folk are champing at the bit to *debunk* positional data extracted from video. Which is just weird. Especially without actually referencing any of the actual data. There's continnual doubt about whether I;m being honest, and yet the data is freely available and I;ve described in more than enough detail how folk can replicate the data themselves. No-one has to trust me in the slightest, but if they say I'm wrong or my data is incorrect it would be kinda handy if they'd show me some of it, or their own, and say look...wrong. But that doesn't happen
The trace data is great quality, the derived data also pretty good given the inherent noise level in the raw data and the conclusions are not such that folk should be jumping up and down in the slightest. Sigh.
Yeah, all fine. At the risk of starting a snowball...the very early motion data shows motion SO early that it's difficult to fit the column 79 stuff into a frame of reference, but time will tell. Need to do the *flexure* traversal traces...at some point.
Most here are bizarrely convinced that is my nefarious scheme, even going so far as to call it propoganda
* BUZZ*
Wrong again!
The problem here is:
Why are you posting all this in the 911 CONSPIRACY sub-forum?
No one has a legit prob with NIST being fleshed out.
If that is truly your desire. I think you chose the wrong audience! Maybe it's just me?
My point has repeatedly been that the analysis made by NIST on the fall speed was already too overkill given their objectives, and therefore attempting to get better data was out of their scope. Your claims of sloppiness are not justified. Their main focus was not the speed of fall, that was a very accessory study that I don't think was necessary for their purpose.From WTC7 trace data, all sorts of things. Early motion data has been very useful. Determining initial flexure
However, if gathering better data helps in any way to draw different conclusions to those they reached, then things could change. But those conclusions need to be reached by competent people in the structural engineering field, or the risk of misinterpreting the data is high. For example, I am not convinced at all that your claims of NIST's sloppiness just for applying their interpretation to the entire north face hold any water, as I think that there may be some engineering assumptions implied in that application, that you are not able to discern. That assertion and other similar ones fall out of the scope of just providing the data, and that's what I'm criticizing mostly. You are sloppy when calling on their sloppiness.
And if they merely confirm NIST's findings, then there's already the NIST report and there's no need for that data.
Childish.
Incorrect. Quotes can be provided.
a) It's the catch-all for all things WTC.
b) I didn't start the thread, tfk did. He started it because, he was arguing about WTC7 descent timings I provided him with a copy of the trace data. He took it upon himself to attempt to *debunk* it
Continnuing discussion evolved...Again...
NISTs choice of location and methodology for their WTC7 position/time trace is a significant problem for their data because...
a) They misinterpreted initial motion as vertical rather than north-south (as they did not take account of the initial twisting motion visible from the Cam#3 viewpoint).
b) They did not perform perspective correction.
c) They did not perform static point extraction (the removal of camera movement from trace data. Even though the view may look static, it is not.)
d) They did not track a feature at all, but a horizontal position. As the building did not descend completely vertically, but included some east-west movement, their data is actually of a wandering horizontal point, not a feature on the facade.
e) In order to obtain a trace from their initial point to their stated final point they had to *splice* together two traces from completely different horizontal positions, which without taking account of the perspective and distance shearing effects makes the data further skewed.
f) They did not treat the base video data correctly, using an interlaced copy of the video (the actual copy they used is available within the recent FOIA releases. I have the original)
g) They did not perform a per-frame trace, but instead skipped frames, reducing the sampling rate considerably and reducing available data redundancy for the purposes of noise reduction and derivation of velocity and acceleration profile data.
h) They applied their interpretation to the entire north face.
i) It is highly probable they used a manual process to record the trace data, rather than the sub-pixel accurate automated feature tracing methods I employ.
These are some of the reasons their data is shoddy and their method sloppy.
Where in any of these discussions do I mention conspiracy ?
I have started one thread here...
http://www.internationalskeptics.com/forums/showthread.php?t=174429
...and have subsequently had to do the leg-work myself through the process of refining tracing techniques to locate the early motion that the thread focusses upon.
Upon what basis is your viewpoint of an individual actually based ?
(Don't answer that, it's off topic)ozeco41
Philosopher
You don't.
But remember one of the attempts to stop your discussions is the many times repeated claim that unless the topic is "conspiracy" it doesn't belong in this sub forum.
A more ridiculous bit of attempted censorship I have not seen. The idea that technical discussions do not belong here is silly enough and totally at odds with the historic practice of this sub forum. No one familiar with the discussions in this forum could seriously suggest that technical stuff has even been discouraged let alone barred.
Likewise look at the amount of thread discussions we would have to curtail if this "conspiracy only" was to become the rule and technical stuff without conspiracy becomes verboten....
...the old saying "cut off your nose to spite your face" comes to mind.
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Supporting this opinion is the fact that the datapoints on figure (12-76) are not equally spaced...
In contrast, my data is sampled at a constant 60*1000/1001 Hz, resulting in inter-sample spacing of 0.016683s
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Again:
The care they put in their analysis is justified by their objectives, and I'm of the opinion that it still was too much.
And again:
You don't have a valid justification to claim this is a mistake. Or to assert that their wording is sloppy when they talk about free fall for about 2.25 seconds. As a remainder, your graph shows that the acceleration was within 32.5±7.5 ft/s² for about 2.25 seconds, therefore in the lack of any error analysis you can't validly claim NIST is wrong.
W.D.Clinger
Philosopher
Although femr2's graph agrees with the leading digit of NIST's stated 1g for about 2.25 seconds, I thought he had a valid quibble about NIST's trailing digits.
That was before femr2 explicitly denied Oystein's suggestion that femr2 has been talking about the trailing digits:
Summary:
- NIST's leading digit agrees with femr2's numbers.
- femr2 decries the interpretation that he is complaining about NIST's trailing digits.
- femr2 says NIST's numbers are "wrong".
ozeco41
Philosopher
Could be but I doubt that it is possible to explain it AND be understood by most people posting in this thread.
I am sure the clue is that too many are making claims within their own frame of reference - their own implied context. And genuinely expecting that others have the same frame of reference. They don't. And some are manipulating that factor as a debating tactic.
Certainly if we filter out all the 'noise' wordage it would help. Then again I speak of something akin to the likelihood of aeronautical exploits by members of the family suidae.
W.D.Clinger
Philosopher
That could be.
femr2 wrote this on 26 April 2011:
The leading digit of femr2's own data agrees with NIST's statement.
On 28 April, femr2 explicitly denied any concern with the trailing digits.
If that was just a debating tactic, it was a remarkably foolish debating tactic. He knows his posts remain within the JREF Forum archives and can be quoted.
ozeco41
Philosopher
I don't want to do a complete detailed review of the thread to put the frames of reference around every related post - it would be a lengthy exercise complete with risk of subjective errors. However, and with due respect I suggest that you have framed all of your claim within your own frame of reference.
And I also don't want to go further by identifying who is using 'tactics' as trickery except Femr2 isn't one. I suggest however that any person who takes one of femr2's claims that 'NIST is wrong' made in the context of this current discussion and misrepresents it that femr2 is making a global claim that NIST's overall explanation is wrong is being mischievous at least. In the current discussion in this thread it is clear in context that femr's statement is limited specifically to the context of the measurement of a portion of WTC7 movement.
I am suggesting that each of us should be alert to that sort of deceptive tactic and either call those who use it or take the bit of mendacity into account in our responses. For his part femr2 has been and continues to be explicit as to his own frame of reference so I don't include him in the group using tactics. There are two areas where he leaves himself open to misinterpretation IMO - I suspect most people will see it as two aspects of the same issue.
The first is when he says without qualification thinks like 'NIST is wrong' and does not keep reminding us that it is only about this bit of data in this context. He should not have to make the qualification - it is clear in context - but since it is known that he will be read out of context and misrepresented it could be prudent to do so. However that is my judgement of what I would do if it was me - he can and does make his own calls. (Otherwise I would be making the error I am trying to describe - interpreting someone else's actions by my own frame of reference.
) Second is that when he says 'NIST is wrong' he means 'wrong by the standards that I, femr2 expect and set for myself'. Again it should be clear in context and that is the point that pgimeno has made - that NIST's work could be good enough for NIST's purposes. (BUT not pgimeno's additional claim that NIST went too far which is applying pgimeno's standard not NIST's)
W.D.Clinger
Philosopher
double standards = twice as many standards
He basically admitted as much in this exchange:
You're free to argue that femr2 deserves a pass because he prefers to post at a JREF Forum instead of publishing a document of professional quality.
Nevertheless, when femr2's writing is judged by the same standard he has set for NIST, femr2's posts have been
Agreed.
Since you suggested it so nicely, I'll call you on your second point.
That highlighted statement is incorrect. femr2 is holding NIST to a higher standard than he has set for himself.
He basically admitted as much in this exchange:
It's perfectly okay for femr2 to leave out the caveats necessary to justify a statement such as
On the other hand, when someone else, such as NIST, fails to place an explicit caveat in front of every phrase, it's
Note that femr2's primary criticism of the passage he quoted is that NIST failed to use the word "approximately" for a third time in front of "gravitational acceleration". That omission is the basis for femr2's repeated assertions that NIST was "wrong" to claim acceleration at 1g. Note also that femr2 is the person who has been inserting the word "exactly" in front of "gravitational acceleration".
You're free to argue that femr2 deserves a pass because he prefers to post at a JREF Forum instead of publishing a document of professional quality.
Nevertheless, when femr2's writing is judged by the same standard he has set for NIST, femr2's posts have been
Those are femr2's words, not mine. In my opinion, after taking femr2's choice of publishing venue into account, femr2's writing has often been hypocritical, boring, and/or sloppy, but has not always been nonsensical. His recent argument became nonsensical only when he augmented his misinterpretation of NIST's statement with his indignant denial of interest in trailing digits.